For quite a while now, we have had many, many customers store their Curio project files directly to their Dropbox folder so they can quickly and easily sync their projects between multiple Macs.

Recently, however, we've had a handful of customers who have experienced a very odd issue with their Curio projects. It's almost as if some of the data within the project spontaneously rolled back to an earlier version. Idea spaces are suddenly gone and replaced with older versions of the idea space.

One common element for these customers is that they were storing their projects directly to their Dropbox folder.

While researching this issue I stumbled across a few other threads where other applications were having occasional issues with Dropbox syncing package files, including this thread over at Scrivener regarding their .sriv package files.

Package files? A Curio project file is actually saved as a package file. On the Mac this appears as a single file, however it's a actually a special kind of folder containing files (such as project assets) and other folders. Package files are natively supported by Mac OS X and is a technique used by many other applications as well. (In the Finder, right-click on a Curio project file and choose Show Package Contents to see what's inside.)

It could be that some of the files within the project package file weren't completely synced and that would cause a problem when Curio re-opened the project.

Some very important guidelines to follow when storing your Curio files to Dropbox:

Make sure you're running the latest Dropbox Mac client. Currently it doesn't appear to let you know if updates are available. To find our what version you have click on the Dropbox menu icon, choose Preferences, then click on Account. At this time the current version is 1.0.28. You can grab the latest Dropbox client here.

Never, ever open the same Curio project on more than one computer at a time.

Completely quit Curio on one machine before opening it on another to guarantee that all file changes have been committed to disk.

Make sure Dropbox has an opportunity to completely sync the changes up to the cloud. If you made lots of changes, added large assets, or have a huge project then this can take a while. The Dropbox icon in the menu bar will show an incredibly tiny animating graphic when it is syncing changes to the cloud. Wait for it to finish animating before putting your machine to sleep or shutting it down.

Do not open the project before your Dropbox folder is fully synced. When you start your machine or wake it from sleep make sure Dropbox is done syncing the changes back down from the cloud. Once again, just watch their little animating menu icon before launching Curio and opening your projects.

While these guidelines should help you work with Dropbox, remember that all products, services, and clouds aren't 100% perfect. So please make sure to follow common sense backup advice with all your important projects and data. Personally I use a combination of Time Machine, MobileMe Backup, cross-machine rsync replication, and Dropbox for all of Zengobi's most important items.